


Angelic Heat

by Substiel



Category: Supernatural
Genre: Angel/Demon Relationship, Angel/Demon Sex, Bottom Castiel (Supernatural), Bottom Castiel/Top Dean Winchester, Dean Winchester Bears the Mark of Cain, Demon Dean Winchester, Implied Mpreg, Light Dom/sub, M/M, Mating Cycles/In Heat, Top Dean Winchester
Language: English
Status: Completed
Published: 2019-05-27
Updated: 2019-05-27
Packaged: 2020-03-20 10:53:39
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,920
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18991225
Author URL: https://archiveofourown.org/users/Substiel/pseuds/Substiel
Summary: How can an angel in heat resist Dean? Not his normal Dean Winchester. A twisted version of him. A demon.





	Angelic Heat

**Author's Note:**

> This one shot has been sitting on my laptop for a while, and I finally decided to post it. Kudos and comments are appreciated thank you.

Castiel felt the first signs when he was overcome with cramps. It always started like this; the pain in his lower body as it prepared itself for the worst. He ignored it and continue to listen to Hannah who hadn’t noticed anything out of the ordinary. He had totally forgotten what she was babbling on about as the pain continued. He balled his hands into tight fists and took a deep breath to calm himself down.

Then it was gone. Castiel let out a breath and unclenched his hands. Hannah continued as if she didn’t notice or didn’t care. Why would she? They were just working together. They weren’t family anymore. Not after the rebellious act, Castiel pulled so many years ago. Why did it hurt so much to think about it now?

Oh, right. His upcoming heat is making him feel this way. He huffed in frustration. He needed to go somewhere safe before his emotions and need to overcome him.

“Castiel. Are you even listening?” Hannah asked with annoyance.

Castiel looked up at her and smiled sheepishly. “I apologize, Hannah. My thoughts are somewhere else. It’s it’s not what y-you think!” He fiddled with his fingers and tugged at the sleeves of his trench coat. The glower Hannah gave him didn’t help the situation at all. He wished he could tell her but he knew she will take him to heaven. He shivered at the thought. He didn’t want to think about what they would do to him for his betrayal and other things…

“Really? Because it seems like you rather be somewhere else than be talking to me about our plans.” Hannah crossed her arms and huffed. “Metatron is still at large. We can’t slack off now.”

“I know that. I just need...time.” Castiel frowned and took a small step back. Before Hannah could respond with a rude comment his cell phone started to ring. She rolled her eyes and climbed into the passenger’s seat of the pickup truck Castiel drove her in. He was filled with remorse and he groaned.

_ “This wasn’t your fault. Metatron tricked you into doing the wrong thing.” Dean said firmly with that beautiful smile Castiel loved so much. _

It wasn’t his fault. Yet, he couldn’t shake the feeling off. Most of the angels didn’t have their wings anymore. He was the very few who still had them only because he found his grace.

The ringing continued until he grabbed his cell phone from his pocket. Sam’s name flashed across the screen and the angel answered it. He held it against his ear and greeted the younger Winchester with a “Hello Sam.”

“Hey, Cas…” Sam greeted back. He sounded tired, and by the tone of his voice, Castiel could suspect he was crying. He frowned.

“What’s wrong?” He immediately asked and glanced back at the pick-up truck where Hannah was waiting.

“Uhm…” There was some shuffling before Sam returned. “I have bad news.”

“Obviously,” Cas murmured a bit bluntly. He squeezed his eyes shut and sighed. “Sorry about that. What is the bad news you speak of.”

“Dean’s dead.”

Those two words took a toll on Cas. His knees wobbled and he gripped onto the truck before he could collapse. He felt grief and sadness take over him as his breath hitched. His eyes welled up in tears and he felt his throat closing up when he refrained from crying. He would not cry. Not right now. It wasn’t the right time to do so.

He cleared his throat. “Where’s his body?”

“Yeah, about that. There’s more. The mark turned him into a demon. I don’t know where he is. One second I was staring into his black eyes the next he was gone. Apparently, he’s bunking with Crowley now. The man himself told me.” Sam sighed.

Cas could hear the sadness in Sam’s voice but couldn’t bear to think of the possibilities Crowley would be teaching Dean at this moment. He was certain Crowley would make Dean do his dirty work. That’s if Dean was willing which most likely wasn’t. The man had too much pride. It frightened Cas on what Dean would do with his new form that held no boundaries or feelings.

Cas rubbed a hand over his eyes and bowed his head. What was he going to do? He practically didn’t have a job anymore. He failed to protect Dean by keeping him from becoming the one thing they all hated the most. A demon. Not just any demon. A knight of hell.

“I’ll come to the bunker. We’ll figure out how to find Dean and turn him back. There has to be a way.” Cas said with a determined voice.

“I hear you. I’ve already started. I just wanted to tell you since you haven’t come to the bunker in a while.”

Cas bit his lip and leaned against the truck. He had been preoccupied with Heaven he hadn’t considered visiting the brothers. Maybe Dean becoming a demon would’ve been prevented if he cared just a little more. “I know. I’ll see you in a bit.” Cas ended the call and dropped his phone into his pocket. He looked back at Hannah and thought about what to do. He had to make a choice; help to rebuild heaven or to find Dean.

He knew the answer from the start of the phone call. Why would thinking about this make any difference? He will always choose Dean. With one look at Hannah, Cas turned around and flew away, leaving her behind.

Cas landed in front of the doorway that opened to the bunker and headed inside. The atmosphere gave him goosebumps and an uncomfortable feeling he could sense. It was traces of new power, most likely scattered around the globe from Dean’s transformation. He didn’t think he could take it if he came face to face with Dean right now. When he entered the library he let out a sigh of relief when he only spotted Sam. The man was hunched over a stack of books and his laptop showed footages from security cameras.

“Hello, Sam. You don’t look well.” Cas observed the messy room as he sat down.

Sam chuckled harshly. “Yeah, you can say that. I’ve been trying to find what we can do for Dean. So far, nothing.” He gestured to the laptop. “I haven’t seen a glimpse of him either. He knows how to drop out of the map with no problem.” He sighed.

“We’ll get him back. We’ve faced bigger threats”

“But not this. It’s not some person we hardly even know. It’s Dean.” Sam exclaimed and dropped the book he was holding on the table. Cas jounced at the loud sound that echoed throughout the room and felt his face burn in embarrassment. The heat was making him jumpy at any loud noise. Thankfully Sam didn’t notice.

“I know, and I get it. He’s family. He’s our...brother.” Cas rebuked through gritted teeth and stared down at the stack of books. It physically pained him to say the word out loud. That’s all they’ll ever be...brothers, friends. Dean made it clear, and Cas numbly agreed while burying his feelings deeper. “I have faith we’ll find him before he does any permanent damage as a creature from hell,” he continued.

“We need a whole lot of faith then,” Sam reminded. He went back to the books without another word.

Cas frowned as he reached forward and grabbed the first book on the stack. He might as well help Sam with research. He ignored the newfound pains that started up again. The words in front of him blurred together from the amount of pain he was in. He tried to hold it in and shielded his face with the book. His first thought was possessing a female vessel to make his heat easier but decided against it. He wasn’t worth putting another woman’s life at risk, so instead, he dealt with the pain. His nails dug into the cover of the book as he breathed in deeply through his nose.

Cas started to get hot and sweaty and all he wanted to do was strip on the spot. He glanced over at Sam who was too preoccupied with the books to notice. The angel set the book down and clicked away on the laptop quickly. He used his grace to speed read through the articles until he found what he was looking for. “Look, Sam.” Cas’ voice was raspy when he spoke and turned the laptop to the hunter. He cleared his throat before speaking again. “I believe a case would be good for you. Sitting here and doing nothing won’t fix anything. You should go. I’ll stay here and keep searching for Dean.” He pried his hands away from the laptop and gripped the table in a white knuckle grip.

Sam looked skeptical as he skimmed through the article with a bit of interest. He glanced at Cas then back at the screen with a sigh. “I guess you’re right. People need saving.” He closed the laptop and grabbed it before standing up. He turned towards Cas. “Thank you for this. If I didn’t have you I would be here all day.” He chuckled.

Cas smiled. “I’m glad you called me. Now, go before you change your mind!”

Sam nodded eagerly. “I have a duffle bag in one of the old cars. Call me if you find anything. I’ll be back in a couple of days.” He slipped on his jacket and headed out of the library.

Once the younger Winchester was gone Cas finally felt he could breathe. He stood up and paced around the room. He shed off his trench coat and navy blue tie. He unbuttoned the first couple of buttons of his dress shirt and rolled up the sleeves. He kicked off his shoes and socks and continued pacing around the room barefooted. He felt like he was going to burst into tears from the pain and heat. His body was still getting ready for the heat even though it was useless. Nobody was going to help him through it. No one did in the past anyway.

God, it was so much easier in Heaven when he wasn’t occupying a vessel but he couldn’t go back. Ditching Hannah must’ve been the last straw for them.

Cas’ white dress shirt stuck to his skin and he huffed. He walked to the bathroom and turned on the cold water. He stripped off the rest of his clothing before getting under the spray. The icy cold water helped cool off his skin for a bit. He sighed in content and leaned his forehead against the cool tile. The pain became bearable after a while and he didn’t feel like he was going to cry anymore.

He stayed under the spray until he was completely cooled off. He turned off the water and stepped out of the tub. He grabbed a towel and dried himself as he made his way into Dean’s room. Since the demon was out and about Cas figured he wouldn’t mind if he borrowed Dean’s clothes. He searched for the most comfortable clothing the hunter owned and decided on a baggy t-shirt and a pair of loose sweatpants. He pulled them on quickly before returning to the map room.

Cas was okay for a couple of minutes until the heat hit him at full force. His knees buckled and he gripped the map table before he could collapse onto the ground. “Fuck!” He screamed. He wrapped his arms around his stomach and dropped his head on the table. His body made the last few changes that left him panting and falling to the floor with a loud thump. Cas’ eyes furrowed in pain as he finally let the tears fall. He curled up into a ball and cried silently.

The pain went on for a couple of minutes before it vanished. Cas sighed in relief and sniffled as he wiped away the tears. He gripped the table and stood up from the floor with a groan. Just as he thought the torment was over he heard a gruff voice behind him that made his whole body twitch and shiver.

“Heya Cas.”

Cas squeezed his eyes shut and whimpered when the footsteps came closer. Why did Dean decide to show up right now? Cas wouldn’t control himself with someone so close to him. Not to mention it was  _ Dean  _ who’s close to him. He couldn’t handle the rejection during his heat. He was fearful he would  _ force  _ Dean. His body started to shake from his cruel thoughts, so he ran. The bunker was big so he had many places to hide away.

Cas could hear Dean’s stomps behind him which filled him with anticipation and excitement of being chased. Just as he was about to enter a room Dean stopped him and pinned him to the wall. Cas bit back a moan and avoided Dean’s gaze. Fingers gripped his chin and lifted his gaze towards the soulless black eyes that stared back at him.

The sob that broke out of him surprised them both and Dean’s eyes were back to their beautiful green. Cas struggled against his grip but the demon pinned him with all his weight. Powerless. Against a knight of hell.

Dean leaned forward and breathed in deeply. “You’re in  _ heat.” _

Cas shivered and bit his lip. He had forgotten about the effect it would take on others. They would immediately know he’s in heat to make the process easier and faster. Dean didn’t even know what he was talking about and Cas felt horrible. “Dean...let me go...please.”

“Don’t you need help?” Dean lifted his head to look at Cas.

Cas shook his head and leaned away. “You don’t want this. You don’t want me. You just want a body to fuck.”

“Of course I do, baby. I’ve always wanted you. My human side just refrained me from getting what I wanted.” Dean growled softly.

“Then you’re not Dean,” Cas whispered miserably.

“I am. I’m your Dean. Just better.” Dean grinned.

“You’re not the same,” Cas cried silently.

Dean wiped away the tears gently and stayed silent. He petted Cas’ hair until the weeping angel calmed down. Cas was shaking from all the emotions he was feeling. The petting made his knees wobble and he would’ve fallen to the ground if it weren’t for Dean holding him. The gesture made Cas want to submit to the demon. Dean cradled Cas’ head and pulled him in for a slow kiss. Cas immediately melted into the embrace and sighed softly as he kissed back. It was gentle and passionate. So much electricity going through his body at the new sensation.

When the kiss ended Dean stayed close and leaned his forehead against Cas’. “I’m still here,” he whispered. “Believe me or not but I need to help you. You’re in pain. Let me make you feel better.”

Cas pondered Dean’s request. This was what he always wanted even though it was a twisted version of Dean. Despite the transformation, he would never deny him, and the pain was differing to need. He needed to be fucked and filled. He peered up at Dean’s beautiful face and make his decision; he cupped his cheek. “Take me,” he murmured.

Dean smiled and planted a kiss on Cas’ lips. “Up.” He patted Cas’ thighs and the angel jumped just in time for Dean to catch him. Cas wrapped his legs around him and held on tightly as they walked to Dean’s room.

Dean made sure to pamper him with kisses at every patch of skin he can reach. They fell into bed with Dean on top of Cas. The weight and rough material of Dean’s clothing made Cas’ skin prickle with need. Dean kissed him slowly as he moved to shed off Cas’ -more like Dean’s- sweatpants. Cas helped with lifting himself off the bed to take off his t-shirt. The angel laid out naked in front of Dean and he licked his lips at the appealing sight. Cas blushed at the attention he was receiving and turned his head to bury his face into the pillow. He squeezed his thighs together and Dean gripped his knees.

“Don’t try to hide away from me, angel.”

Cas shivered and felt himself grow hard because of Dean’s sonorous voice. The demon gently pushed his legs apart and Cas heard his breath hitched. He lifted his head off the pillow and leaned on his elbows to peer up at Dean’s surprised face. Suddenly, he felt farouche and tried to squirm away from Dean. He couldn’t bear to witness the disgusted look Dean will have upon the new discovery.

But Dean didn’t let him get far.  He gripped Cas’ thighs and pulled him closer until his ass touched Dean’s pelvis. Cas gasped when he felt Dean’s large cock poke at his leaking hole. He gripped the sheets to refrain himself from bucking his hips. All he wanted was Dean’s cock inside of him. He didn’t care how Dean would use him just wanted to be  _ filled. _

Cas wanted to forget the shame that took over him upon the change his body took to get ready for his heat. That’s all that heats are for; producing fledglings. All he needed was Dean’s cum inside his slicked hole and he’ll be pregnant after his heat. He didn’t want to know what to think of it. Would Dean even want the baby? If he didn’t, Cas would be crestfallen but would still keep the child no matter what. He’ll deal with it later. For now, he just needed to persuade Dean to go faster.

“Are you going to fuck me?” Cas asked innocently.

Dean groaned and dug his fingernails into Cas’ meaty thighs. He rubbed the angel’s hole and groaned again at how wet Cas already is. He could easily fit two fingers inside him and chuckled. “You’re soaked, baby, and we just kissed.”

Cas ducked his head and flushed in embarrassment. Dean just seemed amused and Cas noticed his dilated pupils. He could barely see the beautiful green hues. He nibbled at his bottom lip at the thought of Dean being turned on by Cas’ body. He felt a spark of frisson and shook from the strong emotion.

“Please, Dean! Fuck me!” Cas cried and threw his head back to reveal his unmarked slender neck. Dean hoped to change that when this is over. He pulled out his fingers and held them out to Cas. The angel looked up at him with his big blue eyes and wrapped his lips around his slicked fingers. Cas moaned at the taste and licked Dean’s fingers clean.

Dean pulled his fingers out and unbuttoned his jeans. He pulled the metal zipper down and shoved his hand in his boxers. He took out his aching cock and stroked it while biting his lip. The pre-cum helped with the friction, and he felt like he could cum with the way Cas laid out in front of him but he stopped. They both wanted this to last. He covered Cas’ smaller body with his own and kissed at Cas’ neck.

Cas wrapped his arms around Dean’s neck and tangled his fingers in the demon’s short hair. He felt Dean’ cock prodding at his own cock and let out a high pitched moan. “Please! I need it!” He cried softly as his thighs shook.

“So impatient, my little cherub.” Dean chuckled huskily. He gripped his cock and pushed the head in. Cas dug his fingernails into Dean’s back and moaned loudly. Dean thrust in and out with only the head of his cock. Cas was still enjoying himself even though he wasn’t getting everything. Dean was careful and wanted Cas to get used to the feeling. He didn’t want to hurt him on their first time together. Being this intimate felt special. Dean had no problem not rushing it.

Every time Dean pushed in he went an inch deeper, and every time Cas would become  _ very  _ vocal. Dean continued his method until his whole cock was buried inside the angel. Cas writhed against him and whimpered softly. Tears of pleasure streamed down his reddened cheeks and he gripped Dean tighter.

“I feel so full. You’re so big, Dean. Ahh. I could feel it.” Cas laid a hand on his tummy and rubbed it with a dreamy sigh. He had a faraway look on his face when he thought about the future. He will grow so big and round with Dean’s child inside him. He can’t wait for that.

Dean gripped Cas’ hips and quickened his pace. Cas’ cock rub against the material of Dean’s flannel so deliciously. The sort of dominance Dean raided with his clothes on made Cas whine and slump against the bed. All he could do was take what Dean gave him and didn’t mind if the demon used him in any way he pleased. Cas was so far gone he just held on for the ride. The slide of Dean’s cock slamming into him and striking his prostate made Cas howl. He wrapped his legs around Dean and dug the heels of his feet against Dean’s back to encourage him to go faster.

“Right there, Dean! Harder, faster. Ugh yes! I love your cock so muchhh!” Cas screamed and buried his face into the crook of Dean’s neck.

Dean rubbed his fingers over Cas’ stretched out hole which made him shook with pleasure.

Dean’s cock and fingers inside him made Cas spill all over himself. He cried out softly and arched his back off the bed as strips of cum covered his belly. He shuddered and shook in Dean’s grasp who didn’t stop moving. Cas grew sensitive at the overstimulation and sobbed. “It’s too much, Dean! Please please please!” He panted.

“Just a little longer, sweetheart,” Dean replied with his raspy voice. Cas felt a bit proud at the effect he had on Dean.

Dean lapped at the dark marks he left on Cas’ neck and he gripped the sheets. Cas heard a ripping noise when Dean came inside him with a groan. Cas’ whole body shuddered when he felt Dean’s warm cum filling him up. He was delirious from the endorphins and whimpered when Dean pulled out of him. The demon laid heavily next to him and Cas immediately launched onto him like an octopus. He gripped him tightly as if the man would get up and leave. He didn’t want that happening anytime soon. Not until the heat was over. All the guilt, sadness, and stress flowed out of Cas and all he wanted was for Dean to stay with him.

After a while, Cas felt Dean’s hand soothing his tense muscles. The rough hand touched his back, sides, neck, and fingers tangled themselves in his sex hair. He giggled at the irony of it and felt Dean’s questioning gaze.

“What are you laughing at?” Dean asked.

“My hair.” Cas’ voice became impossibly deeper and hoarse from all the screaming. He cleared his throat and nuzzled against Dean’s chest. “You always teased me about my sex hair. Now, you’re the cause of it.” He grinned. He traced over the anti-possession tattoo and hummed happily. The afterglow was a sight to see on the angel.

Dean smirked. “Yeah, you’re right.” His arm grew numb after a while but he didn’t care because Cas was already fast asleep.


End file.
